This invention relates generally to a compact or laser disc having a primary memory field for recording information thereon in the form of encoded information in tracks on a surface thereof and more particularly to a compact disc (CD) that contains supplemental memory means outside the primary memory field that is addressable by addressing means in a disc player to read from or write to the compact disc memory means.
Over recent years, the CD has become a mainstay storage memory for playback of recorded audio and visual data, including applications pertaining to text and software. Since this recording is generally permanent in nature, the data had to be considered for playback in the order recorded on the CD. As recognized in U.S. Pat. No. 4,872,151, there was no means for programming the CD per se to dictate the order of play for the data recorded or indication of the parameters and index codes of the recorded data, such as, the number of different recorded data components in the primary memory field, their recorded length and positions of start and ending or other data relating to comments relative to the contents of the recorded data components.
Conventional CD players contain features, such as, an internal memory dedicated to the storing of programming information indicating the order of reproduction of recorded data components in the primary memory field of the CD. However, this type of programming requires introduction of a new programming sequence for CD to be played; otherwise, the order of play will be the same as the program order of play designed and set into the player memory for the previous CD. What is need, then, is some type of supplemental programmable memory associated with the CD rather than the CD player so that the desired order of play of the data components on the CD can be placed in the memory relative to each CD. In this manner, the order of playback desired in connection with each CD can be preprogrammed in the CD requiring no further changes once so prerecorded. However, if the order of replay is desired to be later altered, the altered order of play may be changed in the supplemental CD memory.
Recognizing that conventional CD players lacked means whereby the CD per se provided information relative to the order of data components or other such data which may be automatically recognized and read by the CD player, U.S. Pat. No. 4,872,151 provided means to read the desired order of data components which is stored in memory provided on or in the CD so that the player may thereafter be made to play selections of data components on the CD in the order provided in the CD memory.